Transportation Modeling Forum December 14, 2011 1
Forum Agenda Model Overview: Growth Forecast and Travel Demand Model Transportation Network Development Travel Demand Model Resources 2
Model Overview: Growth Forecast and Travel Demand Model Rick Curry 3
What is a Transportation Model? Mathematical Equations that Replicate Observed Human Travel Behavior Based on Survey Data Assumes Constant Behavior 4
What is the model used for? Transportation System Land Use and Demographics Transportation/ Land Use Policies Transportation Model System Demand Environmental Impact System Performance 5
4-Step Transportation Model Growth Forecast Traffic Census Highway Network Traffic Analysis Zones Travel Surveys Transit Network 1 2 3 4 Trip Generation Trip Distribution Mode Choice Trip Assignment Post-Processing Truck Trip Generation Truck Trip Distribution Air Quality 6
4-Step Transportation Model Growth Forecast Traffic Census Highway Network Traffic Analysis Zones Travel Surveys Transit Network 1 2 3 4 Trip Generation Trip Distribution Mode Choice Trip Assignment Post-Processing Truck Trip Generation Truck Trip Distribution Air Quality 7
Linking Growth Forecasts with RTPs Growth Forecast RTP Base Year Horizon Year Series 5 1980 1978 2000 Series 6 1986 1980 2005 Series 7 1989 1986 2010 1990 1986 2010 Series 8 1994 1990 2015 1996 1995 2020 Series 9 2000 1998 2020 Series 10 2003 2000 2030 2006 update 2000 2030 Series 11 2007 2003 2030 Series 12 2011 2008 2050 8
Regional Results: Population, Jobs, Housing Millions 9 9
Regionwide Age Structure: 1990, 2000, 2010 and 2050 Male Female Source: U.S. Census Bureau, Census 1990, 2000, 2010; SANDAG, 2050 Regional Growth Forecast, February 2010 10
4-Step Transportation Model Growth Forecast Traffic Census Highway Network Traffic Analysis Zones Travel Surveys Transit Network 1 2 3 4 Trip Generation Trip Distribution Mode Choice Trip Assignment Post-Processing Truck Trip Generation Truck Trip Distribution Air Quality 11
Traffic Analysis Zones 12
The Traditional 4-Step Transportation Model Growth Forecast Traffic Census Highway Network Traffic Analysis Zones Travel Surveys Transit Network 1 2 3 4 Trip Generation Trip Distribution Mode Choice Trip Assignment Post-Processing Truck Trip Generation Truck Trip Distribution Air Quality 13
Surveys Travel Behavior Surveys Inter-regional Intra-regional California Household Travel Survey (CHTS) National Household Travel Survey (NHTS) Regional / On-board Transit Surveys Transit Passenger Counting Program Census / ACS / CTPP Cross-Border Surveys Parking Surveys Taxi Surveys Vehicle Occupancy and Classification Surveys Visitor Surveys Market Research Surveys 14
4-Step Transportation Model Growth Forecast Traffic Census Highway Network Traffic Analysis Zones Travel Surveys Transit Network 1 2 3 4 Trip Generation Trip Distribution Mode Choice Trip Assignment Post-Processing Truck Trip Generation Truck Trip Distribution Air Quality 15
Highway & Transit Networks 16
Highway Networks 17
Transit Routes and Stops 18
4-Step Transportation Model Growth Forecast Traffic Census Highway Network Traffic Analysis Zones Travel Surveys Transit Network 1 2 3 4 Trip Generation Trip Distribution Mode Choice Trip Assignment Post-Processing Truck Trip Generation Truck Trip Distribution Air Quality 19
Tracking Model Evolution 20
Changes for 2050 RTP Zones New boundaries for MGRA and TAZ Jurisdiction Network Review Updated for Base Year 2008 Cordons & POE forecasts Airport demand (AMAP) Traffic and transit boarding counts 21
Changes for 2050 RTP Costs Parking costs Transit fares and structure Auto operating costs based on RTAC Mode Choice Model FTA Newstarts update Highway Assignment Additional vehicle classes Stricter assignment convergence criteria 22
4D s Model Enhancements The 4D s Residential and employment Density Diversity of complimentary land uses Neighborhood form: Transit and pedestrian oriented Design Includes Distance to transit Accessibility to Destinations 23
4D Model Enhancements Trip Distribution Trip lengths are more likely to be shorter in dense and diverse areas Mode Choice Trip modes are more likely to shift to transit \ non-motorized in dense and diverse areas 24
Truck Model IE and EI EE II I = Internal E = External 25
Is the model output any good? 26
Validation Report Sensitivity Report Model Reports 27
Model Documentation Series 12 Model Documentation 2050 regional growth forecast 2050 regional travel demand model Related Publications 4D model development Truck model development http://www.sandag.org/models 28
Model Transportation Networks Joaquin Ortega 29
SANDAG Transportation Model Dimensions Spatial 4,682 Traffic Analysis Zones (TAZ) 12 external cordon zones 2,500 Transit Access Points (TAP) Network 34,000 Roadway Network Links 21,000 Roadway Network Nodes 10 Roadway Facility Types 30
Transportation Model Network 31
Transportation Network Data Review Timeline 6 Months Took Place in 2009 Attributes Number of Lanes Facility Type Posted Speed Intersection Controls Data Sources 2008 Base Year Aerial Photos EIRs and site plans Local General Plans / Circulation Elements Regional Transportation Improvement Program (RTIP) 32
Observed Challenges Ongoing regional growth Land use & demographic forecast frequency Volume of links & nodes Staff time 33
Transportation Model Review Website Allows local agencies to review model network using a web-browser Simple navigation Controlled access 34
Transportation Model Review Website 35
Transportation Model Editing 36
Transportation Model Review Website 37
Total Scope 38
Results Very high participation rate Over 2,000 comments submitted Over 4,000 edits made Project Timeline: 6 months 39
Results Lanes Added or Removed -195 Freeway ramps -155 Prime arterial links -308 Major arterial links -504 Collector links -132 Local street links Intersection Edits -218 Traffic signals added -381 All way stops added -86 Directional stops removed Speed Limit Edits -1,591 Link changes of ± 5 mph -580 Link changes of ± 10 mph -160 Link changes of ± 15 mph 40
Benefits Streamlined calibration process Low cost of web tool development Increased rapport with jurisdictional staff Increased model mapping accuracy 41
Future Application Series 13 forecast Base Year 2010 Enhanced internal checks before soliciting feedback Future year networks 42
Travel Demand Model Resources Mike Calandra 43
Travel Demand Model Resources Model users and uses Model inputs Standard model output Customized model output Downloadable model data Model Documentation External data sources 44
Transportation Model Users Caltrans CARB SANDAG APCD City of San Diego Transportation Model MTS Local Jurisdictions NCTD Private Developers 45
Transportation Model Website http://www.sandag.org/models 46
Model Input Growth Forecast Region-wide Forecast (DEFM) Land Use Plans And Policies Interregional Commute Model (IRCM) Growth Allocation Model (UDM) Transportation Model 47
Model Input Freeway Traffic Census https://pems.eecs.berkeley.edu 48
Model Input Local Traffic Census http://www.sandag.org/resources/demographics_and_other _data/transportation/adtv/index.asp 49
Model Input Local Traffic Census (Coming Soon) 50
Model Input Regional Traffic Count Database (Coming in 2013) A central repository and historical archive of all non-automated arterial traffic counts Interactive mapping application Currently under contract! 51
Model Input - Traffic Generators http://www.sandag.org/uploads/publicationid/publicationid_1140_5044.pdf 52
Model Process 53
Standard Model Output Average Daily Traffic (ADT) 54
Standard Model Output Level of Service (LOS) 55
Standard Model Output Transit Flow 56
Standard Model Output Person Trip End Density 57
Standard Model Output Traffic Forecast Information Center http://gis.sandag.org/tficsr11/ 58
Standard Model Output Vehicle Miles of Travel (VMT) VMT is the key output metric from travel demand models as an input into Air Quality Analysis Calculations Link VMT = ( ADT * Length ) / 5280 Aggregated to regional figures 2008 Base Year 80,316,066 2050 RC 118,309,850 59
Customized Model Output Traffic Distribution Analysis 60
Customized Model Output Travel Time Analysis 61
Customized Model Output Jurisdictional VMT Utilizing existing tools, cities can calculate their VMT for the purpose of conducting sustainable community strategy analyses City-wide Select Zone assignment Compressing trip tables GIS overlays Spread sheet output 62
Downloadable Model Output ftp://ftpx.sandag.org/sandag/pub/series 12/Final/ 63
External Data Sources Institute of Traffic Engineers (ITE) Traffic Management Data Dictionary (TMDD) http://www.ite.org/standards/tmdd/ http://www.ite.org/ 64
External Data Sources Transportation Research Board (TRB) http://www.trb.org/ 65 65
External Data Sources Travel Model Improvement Program (TMIP) http://tmip.fhwa.dot.gov/ 66 66
External Data Sources Caltrans Description of Transportation Models X http://www.dot.ca.gov/hq/tsip/otfa/modeling/descriptiontranspmodels.pdf Statewide Travel Model X http://www.dot.ca.gov/hq/tsip/smb/swmodel.html Travel Forecasting Guidelines X http://ntl.bts.gov/docs/tf.html EMFAC Air Quality Model x http://www.dot.ca.gov/hq/env/air/pages/emfac.html 67
External Data Sources Federal Highway Administration (FHWA) Planning team resource center X http://www.fhwa.dot.gov/resourcecenter/teams/planning/travel.cfm Traffic Analysis Toolbox (TAT) http://ops.fhwa.dot.gov/trafficanalysistools/ 68
External Data Sources Federal Transit Administration (FTA) Travel forecasting for Newstarts X http://www.fta.dot.gov/documents/session_05a(3).pdf National Transit Database http://www.ntdprogram.gov/ntdprogram/ 69
Forum Agenda Recap Model Overview: Growth Forecast and Travel Demand Model Transportation Network Development Travel Demand Model Resources Next Transportation Modeling Forum: June 13, 2012 70
Open Discussion 71
Transportation Modeling Forum December 14, 2011 72